As an optical fiber cutting device, there are two types of device, i.e., a high performance type and a simple type. The simple type device has a structure in which an optical fiber is mounted on a bending plate, the end portion of the optical fiber is clamped and a portion to be cut off is scratched, and then the optical fiber is bent with the bending plate to obtain the cleavage. In the simple type, the operator is required to have a high level of proficiency to obtain an excellent cutting angle, however the cost thereof is low, thus widely used. To connect the optical fiber with a low connecting loss, it is necessary to cut off the optical fiber with an excellent cutting end (i.e., angle to be cut, roughness in the cross section or the like) in all cases including a fusion splicing, mechanical splicing to connect by a connector or the like. Accordingly, the high performance type has been the main stream which can obtain the excellent cutting end without high level of proficiency.
Along with a widespread of a FTTH (Fiber To The Home) to lay the optical fiber to each customer, a simple type of a fusion splicing device to easily handle on the electric pole or in the customer's house or the like appears. However, a required level for the optical fiber cutting device to obtain a desired connecting loss in the fusion splicing or the mechanical splicing becomes higher, thus the high performance type is mainly used. The high performance type optical fiber cutting device can obtain the excellent cutting end of the optical fiber without depending on the high level of proficiency of the operator, and is disclosed for example, in the Japanese Patent Application Publication No. Hei 1 (1989)-112206, or Hei 1 (1989)-126601.
A laying operation of the optical fiber to each of the customer increases, and a large number of the optical fiber cutting devices are required in many sites of laying operation. Since the high performance type optical fiber cutting device is very expensive, the cost becomes remarkably large when a large number of the high performance type optical fiber cutting devices are allocated in each site of the laying operation. It therefore comes to be desired that an excellent cutting end of the optical fiber is to be obtained even for the simple type optical fiber cutting device, which is low cost in comparison with the high performance type optical fiber cutting device, without depending on the high level of proficiency of the operator.
For example, a cutter with a metal blade provided has been conventionally applied, when the optical fiber is cut off in arranging the connecting portion like an optical fiber connector or the like in the end portion of the optical fiber received in the closure placed in the vicinity of the electric pole.
According to the above described cutter, first of all the scratch is made in the optical fiber in a perpendicular direction to the longitudinal axis of the optical fiber, and then the cleavage is implemented. This requires a certain level of high proficiency so that some operator does not cut off the optical fiber in good manner.
Japanese Patent Application Publication Shou 62 (1987)-231203 discloses the conventional simple type optical fiber cutting device. FIG. 33 is a schematic perspective view to show the conventional optical fiber cutting device. The glass portion of the optical fiber is places on the optical fiber cutting device along the longitudinal direction thereof (not shown). The conventional optical fiber cutting device includes a clamp lever 114 supported with axis by a bracket 112a of a support plate 112 to hold an optical fiber (not shown), a bite arm 146 supported with axis by the bracket 112a and provided with a bite block 116, and a tensile bending stress imparting means 120 attached to the support plate 112. The optical fiber is cut off by the optical fiber cutting device, as described hereunder.
The optical fiber with a portion to be cut exposed by removing the coating is placed in an engaging groove 152. The clamp lever 114 is brought upward in resisting to a spring, and the exposed optical fiber is pinched between a rubber plate 124 of the clamp lever 114 and a rubber plat 122 of the support plate 112. Then, the bite arm 146 is pushed down in resisting to a spring 128 so that a bite (blade) of the bite block 116 is pressed through the optical fiber on a rubber layer 142. This causes a cut into the exposed optical fiber. Then, a fiber receiving member 136 together with the optical fiber is rotated downward around a support axis 132 in resisting to a spring 138. The exposed optical fiber is bent at a roller 140 as a fulcrum and imparted a tensile stress to be cut off.
Patent document 1: Japanese Patent Application Publication Shou 62 (1987)-231203;
Patent document 2: Japanese Patent Application Publication Hei 1 (1989)-112206;
Patent document 3: Japanese Patent Application Publication Hei 1 (1989)-126601